Dental treatment appliance



April 11, 1 967 HER Z 3,313,025

DENTAL TREATMENT APPLI ANCE Filed Jan. 20, 1964 I I 5 Sheet-Sheet 1 INVEN TOR.

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United States Patent 3,313,025 DENTAL TREATMENT APPLIANCE Fred Hertz, 166Z1 20th Ave., Whitestone, N.Y. 11357 Filed Jan. 20, 1964, Ser. No. 338,760 15 Claims. (Cl. 32-23) This invention relates to the art of dental treatment appliances and more particularly concerns assemblies having air-driven handpieces with fluid coolant spray means.

According to the invention, there is provided an appliance assembly for dental treatment including a switch and hanger box adapted for supporting one or more fluiddriven handpieces, the box being mountable on a wall, on the back of a dental chair, on an arm swingably mounted on a Wall, on an arm of a dental stand or other support. The box has hangers terminating in hooks or forks arranged so that the handpiece or handpieces will hang vertically in all positions of the box between horizontal and vertical positions. The hangers are spring biased in the box so that when any handpiece is lifted ofi a hanger the hanger is moved by its spring to actuate a switch in the box.

A remotely located air and water distribution box containing three-way solenoid controlled air and water valves may be associated with the switch and hanger box. The solenoids of the valves are connected to one switch in the switch and hanger box. Each valve has an inlet and two outlets. A first outlet is normally connected in communication with the inlet of the valve while the solenoid of the valve is deenergized. The other outlet is connected in communication with the inlet of the valve when the solenoid of the valve is energized to move a core in the valve for closing off the first inlet.

An air and water drive control box is connected to the valves in the distribution box for supplying air and Water thereto. This last control box may have foot-controlled valves operated by pedal pressure applied by a dentist or dental technician. The air and water drive control box may have solenoid controlled valves with inlets connected to suitable air and water supply sources and with outlets connected to the valves in the air and water distribution box. The solenoids of the air and Water drive control box may be connected in circuit with a foot switch or rheostat and with the switch associated with each hanger of the switch and hanger box.

A system may be set up including just one fluid-driven hand-piece, or two, three or more fluid-driven handpieces. The system may be associated with an engine-driven handpiece or may be set up independently of and without an associated engine-driven handpiece.

It is one object of the invention to provide an appliance assembly for dental treatment, the assembly including a switch and hanger box adapted for removably supporting one or more fluid-driven handpieces, with the handpieces vertically disposed in all mounting positions of the box.

A further object is to provide a dental appliance assembly including a switch and hanger box for supporting one or more air-driven handpieces, the assembly being mountable on the swingable arm of an engine support on a dental stand or on a swingable arm carried by any stationary support, which arm can be pushed aside by a dentist to permit a patient to enter and leave a dental chair and to provide the dentist with an unencumbered and unobstructed working area around the patient.

Another object is to provide a dental appliance assembly as described wherein each handpiece is directly connected to air and water supply sources when it is lifted from the switch and hanger box, while any handpiece re- 3,313,025 Patented Apr. 11, 1967 maining on its hanger is cut oil from the air and water supply.

Still another object is to provide an appliance assembly as described with an air and water distribution box having solenoid controlled valves operated by only one switch of the switch and hanger box.

A further object is to provide an air and water distribution box for a dental appliance assembly as described, the distribution box containing solenoid controlled air and Water valves, each of the valves having two outlets and a single inlet, one of the outlets being normally connected in communication with the inlet when the solenoid of the valve is deenergized, and the other of the outlets being connected in communication with the inlet when the solenoid of the valve is energized while the one outlet is closed.

Still another object is to provide a dental appliance assembly which may include physically operated air and water drive valves or solenoid controlled air and water drive valves.

Another object is to provide means for coupling two or more fluid-driven dental handpieces automatically to an air and water drive control box.

Another object is to provide an adapter assembly for a conventional dental stand including a dental engine and belt-driven handpiece, said assembly including a switch and hanger box mountable on a swingable belt drive support arm of the stand and being adapted to support one or more fluid-driven handpieces, so that a dentist has at hand a selection of belt-driven or air-driven handp-ieces, and the handpieces may be conveniently removed from the support arm of the stand in all positions of the support arm.

For further comprehension of the invention, and of the objects and advantages thereof, reference will be had to the following description and accompanying drawings, and to the appended claims in which the various novel features of the invention are more particularly set forth.

In the accompanying drawings forming a material part of this disclosure:

FIG. 1 is a perspective view of parts of an assembly embodying the invention mounted on a dental treatment stand.

FIG. 2 is a fragmentary perspective view of parts of the assembly and dental treatment stand in an elevated position, rotated about from the position of FIG. 1.

FIG. 3 is an enlarged vertical sectional view through a switch and hanger box.

FIG. 4 is a front elevational view of a switch and hanger box supported by a swingable arm on a wall.

FIG. 5 is a perspective view of another switch and hanger box.

FIG. 6 is a sectional View of a solenoid controlled valve such as may be used in an air and water distribution control box. 7

FIG. 7 is a sectional view of a solenoid controlled valve such as may be used in an air and water drive control box.

FIG. 8 is a sectional view of a foot-controlled valve.

FIGS. 9-12 are schematic diagrams of systems embodying the invention.

FIGS. 13, 14 and 15 are block diagrams of systems embodying the invention.

Referring first to FIGS. 1 and 2, there is shown a conventional dental treatment stand 10 having fixed arms 11 pivotally carrying a dental engine 12 and arms 14 connected to the housing of the engine 12. The engine 12 drives a pulley 21. On this pulley is entrained a belt 20. The belt drives idler pulleys 22, 23 and 24. Pulleys 22-24 are carried by arms 14 and pivotally attached links 25, 26. The belt 20 drives a low-speed high-torque handpiece HP. Handpiece HP when not in use is supported on a book 29 on link 26. To the extent described the parts of the dental stand are conventional.

According to the invention, the dental treatment adapter assembly includes a switch and hanger box 39 provided with a clamp 32 so that the box can be mounted near the outer end of movable arms 14 or other suitable support. The box 30 has a movable forked hanger H1 at its underside and another movable forked hanger H2 at its right side as viewed in FIGS. 1, 2 and 3. The hangers operate switches SW1, SW2 in box 30. Fluid-driven handpieces HP1 and HPZ such as described in Patent 3,094,780 are removably supported on the hangers H1, H2, respectively. Air supply pipe 39 and water supply pipe 41) are connected to handpiece HP1. Air supply pipe 41 and water supply pipe 42 are connected to handpiece HPZ. These pipes terminate at solenoid controlled valves in an air and water distribution box 44 mounted on stationary arms 11 of the dental stand, remotely from box 30. The box 30 is located near handpiece HP so as to present the handpieces HP1 and HP2 readily to hand for instant use when required. While it has been proposed heretofore,

as in the above-mentioned Patent 3,094,780, to provide a fluid-driven handpiece for use With a conventional dental appliance installation, no provision was made for conveniently locating the fluid-driven handpiece at the location of the belt-driven handpiece, so that a dentist working on a patient is required to turn away from the patient to reach the fluid-driven handpiece. Thelocation of box 30 near the outer end of arms 14 in the present invention avoids this undesirable situation.

It will be noted that the hangers H1 and H2 have arms 35 and 37 which are disposed in inclined positions with respect to switches SW1 and SW2 when the box 30 is in the horizontal position of FIGS. 1 and 3 or the vertical position of FIG. 2, or in all intermediate positions. The forks of the hangers also extend obliquely laterally so that the handpieces HP1 and HP2 always hang substantially vertically in convenient positions to be lifted off the hangers by a dentist, regardless of the position of the box 30. The arms 35, 37 of the switches :are biased away from the switches by springs inside the switches bearing on switch buttons B1 and B2. Thus, when a handpiece is removed from a hanger the hangers move away from the switches as the switch buttons move outwardly of the switches. The arms 35, 37 pass through slots 39a, 3% formed in the sides of thebox 3t), and move laterally in these slots when the handpieces are removed from the hangers and are replaced thereon.

FIG. 4 shows a switch and hanger box 30 mounted on a swingable arm 45 which may be on a vertical wall W, back of a dentists chair or other fixture. Arm 45 is shown horizontal but can be swung to a vertical position. This will move the box 30 from the vertical position shown in solid lines to the elevated out-o-f-the-way horizontal dotted line position. In both the lowered and elevated positions, the handpieces HP1, HP2 hang vertically from the hangers H1, H2 and can be conveniently grasped for removal from the hangers. The arm 45 is engaged in a clamp 46 carried by mounting bracket 47, when in vertical position.

A cable 50 terminates at box 30 and has wires connecting the switches SW1, SW2 to external circuits to be described. The wires from one switch may be connected to the solenoid valves in the distribution box 44. The wires from the other switch may be connected to solenoid valves in an air and water drive control box 51 such as shown in FIG. 9. Air and water pipes or conduits 52, 53

preferably made offlexible, plastic tubing, connect the air and water drive control box to the distribution box 44.

FIG. shows a switch and hanger box 30' having a single movable angularly disposed forked hanger H3 extending obliquely outward thereof for mounting a single fluid-driven handpiece HP3 thereon. This box has a cable 50' which may be connected in circuit with components in a remotely located control box such as box 44,

A bracket 32' is provided to mount the box on a support at a dentists work position.

FIG. 6 shows a three-way valve 60 of a type which may be used in the air and water distribution box 44. This valve has a valve body 60 with an inlet 61, outlet 62 and outlet 63. Inlet 61 is in continuous communication with outlet 62 via a central passage 63 when solenoid 64 which surrounds movable core 65 is deenergized. The core is held retracted in the passage 63 by a coil spring 66 bearing on a disk 67 attached to a stem 68 secured in the lower end of core 65. The upper end of the spring bears on a flange of a valve sleeve insert 69 screwed into passage 63. The stem 68 passes through the upper end of the insert. A transverse passage 70 is formed in core 65 and aligns axially with inlet 61 and outlet 63 when the solenoid 64 is energized. At the same time the outlet 62 is closed by core 65. The air and water distribution box 44 has two such valves for controlling distribution of air and water respectively. The details of the valve 66 as described are only exemplary since it will be understood that other equivalent solenoid controlled valves may be provided.

FIG. 7 shows one type of solenoid controlled valve which may be used in an air and water drive control box to regulate supply of air or water to a distribution box or handpiece. This valve has an inlet 81 normally closed off from outlet 82 by a movable core 83. When the solenoid 84 in the valve is energized, the valve core 83 moves upwardly against the bias in spring 85 to align transverse passage 86 with the inlet 81 and outlet 82.

FIG. 8 shows one type of physically controlled valve I 90 which may be used to regulate or control supply of air or "water to an air and water distribution box or to a handpiece. This valve has a piston 91 with a pedal 92 which may be foot-operated. The piston moves in the valve body 93 against tension in spring 92 to align transverse passage 94 in the piston with the inlet 95 and outlet 96 of the valve. The piston is held in the valve body by a pin 97 engaged in a slot 98 in the piston.

FIGS. 9-15 show schematically and diagrammatically various systems which may include any one or more of the switch and hanger boxes 30, 30'. The systems may employ one or more air and water distribution boxes 44 having three-way valves as described above. In all of these systems, a dentist has means providing instant and automatic coupling of any selected fluid-driven handpiece to controllable sources of air and water while all otherv non-selected handpieces are cut off from the air and water sources.

Referring first to FIG. 9, the system S1 includes the hanger box 36 containing switches SW1 and SW2. Switch SW1 is a single-pole double-throw switch having pole 101) normally closed with terminal 101 when the handpiece HP1 supported on hanger H1 causes arm 35 to press button B1 inwardly of the switch. When the handpiece is removed from the hanger spring SP1 raises the button, pole, arm and hanger so that pole closes with terminal 102 of the switch., Switch SW2 is a double-pole double-throw switch. Pole 104 is closed with terminal 105 and pole 166 is closed with unconnected terminal 107 when handpiece HP2 is hung on hanger H2 so that arm 37 depresses button B2 and poles 104, 106. When handpiece HP2 is removed from the hanger H2, spring SP2 will raise the button, arm and hanger and pole 104 will close with terminal 108 while pole 106 will close with terminal 110.

The system includes air and water distribution box 44 in which a three-way air valve 60a like valve 60 of FIG. 6 has its solenoid 64a connected in parallel with solenoid 64b of another three-way water valve 60b like valve 60, to power supply terminal 112. The solenoids are also connected to pole 106 of switch SW2. Terminal 110 is connected to power supply terminal 114. Thus the solenoids will be energized only when switch SW2 is actuated by lifting handpiece HP2 from hanger H2.

The air inlet 61a of valve 60a is normally connected to outlet 62:: when solenoid 64a is deenergized. Outlet 620 is connected via air line 39 to handpiece HP1. Outlet 63a is connected via air line 41 to handpiece HP2. Air inlet 61a is connected via air line 52 to outlet 82a of a solenoid controlled air valve 80a. like valve 80 of FIG. 7, in an air and water drive control box 51. The inlet 81a of the valve 80a is connected to an air supply 120 at suitable air pressure. When solenoid 64a of valve 60a is energized, the valve core 65a is moved to close outlet 62a and connect inlet 61a to outlet 63a.

Water inlet 61b of valve @012 is normally connected to outlet 6211 when solenoid 64b is deenergized. Outlet 62b is connected via water line 40 to handpiece HP1. Outlet 63b is connected via water line 42 to handpiece HP2. Water inlet 61b is connected via water line 53 to outlet 82b of a solenoid controlled water valve 80b like valve 80 in box 51. The inlet 81b of valve 801) is connected to a water supply 122 at suitable water pressure. When solenoid 64b of valve 6% is energized, the valve core 65b is moved to close outlet 62b and connect inlet 61b to outlet 63b. 7

Pole 160 of switch SW1 is connected to power supply terminal 114. Terminal 101 is connected to pole 164. Terminal 105 is connected to dental engine 12 which drives handpiece Hi The dental engine is connected via a rheostat 124 in a foot control 126 to power supply terminal 112. It will thus be apparent that when the handpieces HP1 and HP2 are on their hangers the power supply circuit for the dental engine is continuous through switches SW1 and SW2. However, if either handpiece is lifted from its hanger the power supply circuit for the dental engine will be broken.

The switch terminals 102 and 110 are both connected via wire 125 to both solenoids 84a and 84b of valves 80a and 80b in the air and water drive control box 51. The solenoids in turn are connected via rheostat 124 to power supply terminal 112. By this arrangement, when either handpiece HP1 or HP2 is selected and lifted from its hanger the air and water valves 80a and 80b are operable under control of the foot control 126.

System S1 is so arranged that lifting handpiece HP1 from hanger H1 has no effect on the position of the cores in valves 60a, 60b of the air and water distribution box 44. The air and water supplied to the handpiece is supplied directly through the air and water drive control valves 811a, 8012, subject to operation of the foot control 126. If handpiece HP2 is lifted from its hanger instead of handpiece HP1, then the valves 60:: and 6% are energized and the outlets 62a, 62b are closed while outlets 63a, 63b are opened and air and water is supplied only to handpiece H1 2.

The system S1 is associated with dental stand 10 of FIG. 1 and employs a common foot control 126 for the handpieces HP1, HP2 and engine 12. The handpieces can be two identical high-speed handpieces in which different standard burrs are fitted. Alternatively, one handpiece can be of standard size and the other can be of miniature size. Also, one handpiece can be of a highspeed low-torque type and the other can be a low-speed high-torque type. The variable foot control 126 will make it possible to regulate the speed of the low speed handpiece.

FIG. 10 shows a system S2 which is similar to system 51 except that the dental engine and power supply circuit for the dental engine are omitted. Parts corresponding to those of system S1 are similarly numbered. The system S2 employs a double hanger box 34 in association with an air and water distribution box 44. Air and water drive control box 51a employs foot regulated valves 90a and 90b like valve 90 for controlling the flow of air and water through the solenoid controlled valves 69a, 60b to the handpieces.

In system S2, handpiece HP1 employs the hanger H1 solely as a mechanical support and does not operate the switch SW1 electrically. This handpiece is supplied with air and water from outlets 62a and 6212 through the direct connections to the inlets 61a and 61b when the valves 60a, 6011 are deenergized. The valves a and 90b are used to turn on, cut off and control the flow of air and water to the handpiece from the air and water supplies 120, 122.

Switch SW2 of system S2 has pole 106 cont-acting unconnected terminal 107 when the handpiece HP2 is on hanger H2. When the handpiece is lifted from hanger H2, pole 106 closes with contact 110 and the solenoids 64a, 641: are energized to actuate the valves and close outlets 62a, 62b while outlets 63a, 6311 are connected to inlets 61a, 61b. The valves 9%, 90b regulate the How of air and water to handpiece HP2 for high speed or variable low speed operation, as foot pedals 92a, 92b are depressed. These foot pedals may be connected together for simultaneous operation if desired, as indicated by connection 130.

FIG. 11 shows a system S3 in which a single handpiece HP3 is removably supported on hanger H3 of switch and hanger box 30. In this box is switch SW3 which is a single-pole double-throw switch. Pole 132 is connected to terminal 112 of the power supply. The pole is in contact with terminal 134 when the handpiece is on the hanger H3 and spring SP3 is compressed. When the handpiece is removed, pole 132 contacts switch terminal 136. Terminal 134 is connected to the dental engine 12' which drives handpiece HP. The engine 12' is connected to the rheostat 124 in the foot control 126' which is connected to power supply terminal 114'. It will be noted that the power supply of the dental engine is thus normally closed through pole 132 and terminal 134. Thus the engine can be operated by actuating the foot control 126. When handpiece HP3 is lifted from hanger H3, the power supply to the engine is opened.

Terminal 136 is connected to the solenoids 84a and 84b of air valve Stla and water valve 8% in an air and water drive control box 51 such as used in system S1. Air is supplied to valve 80a from air supply and water is supplied to valve 8% from water supply 122. The outlets of the air and water valves supply air and water to the handpiece via air and water lines 39, 40. The air and water is supplied under control of the rheostat 124' connected in circuit with the solenoids 84a, 84b.

FIG. 11 illustrates a system in which a single handpiece and a single switch and hanger box are integrated into apparatus including a dental engine and mechanically driven handpiece. The dentist has readily and conveniently at hand a choice of either a fluid-driven highspeed low-torque handpiece or a mechanically driven low-speed high-torque handpiece. The system S3 can be installed as accessory apparatus in an existing installation including a dental engine and foot control.

FIG. 12 shows system S4 which includes three handpieces HP1, HP2 and HP3. The system has a double hanger box 30 and an additional single hanger box 30a similar to the single hanger box of FIG. 5. System S4 is similar to systems S1-S3 and corresponding parts are identically numbered. Hanger box 30a is provided with a double-pole double-throw switch SW3 which is similar to switch SW2 in box 30. An additional air and water distribution box 44 is provided which is similar to box 44. Box 44' has air and water solenoid controlled threeway valves 60a and 60b similar to the valves 60a and 60b in box 44. A novel arrangement is provided for the air and water supply to the handpieces HP1 and HP2. The air supply to valve inlet 61a is provided via an 'air line 140 connected from outlet 62a of 'valve 60a. The water supply to valve inlet 61b is provided via water line 142 connected from outlet 62b of valve 60b. Valves 80a and 80b in the air and water drive control box 51 of the system are connected to the inlets 61a and 61b of valves 60a and 60b.

Handpiece HP3' is supplied with air and water from the normally closed outlets 63a and 63b of the air and water valves 60a, 60b. The foot control 126 may be used to regulate the speed of any low-speed high-torque handpiece employed in the system.

In operation of system S4, if handpiece HP1 is lifted from its hanger H1, air will pass directly from the air supply 120 via air valve 89a, normally open air outlet 62a and normally open air outlet 62a upon actuation of the foot control 126 so that solenoid 84a is actuated to open valve 890. Similarly, water will pass directly from the water supply via water valve 89b, normally open water outlet 62b and normally open water outlet 6211 upon actuation of the foot control 126. The power supply for valves 80a and the foot control is completed via pole 1M) of switch SW1 closed with terminal 102.

If handpiece HP2 is lifted from hanger H2, the valves 80a and 8012 will be energized via pole 104 closed with terminal 108. In addition, the solenoids 64a, 64b of valves 60a, 6% will be energized through contact of pole 106 with terminal 110. The valve outlets 62a and 62b will close while outlets 63a, 6312 will be opento supply only handpiece HP2 with air and water. The air and water pass through the normally open outlets 62a and 62b of valves'fifla' and 60b which are not actuated.

If handpiece HP3 is lifted from its hanger H3, then the air and water supply to valves 60a and 69b is cut olf as valves 60a and 60b are actuated. The solenoids 64a and 64b are energized via pole 106 closing with terminal 110' of switch SW3. The air and water valves 80a and 80b are energized via closed pole 104' and terminal 108. Air and water supply is regulated and controlled by the foot control 126.

A dental engine and mechanically driven handpiece can be included in the system if desired in a manner similar to that illustrated in system S1.

FIG. 13 shows in block diagram form the basic arrangement of system S4. It will be noted that the air and water distribution box 44 is supplied via normally open outlets of valves in box 44 for supplying handpieces HPl and HP2 carried by a double box 30 while handpiece HP3 carried by single box 30a is supplied with air via the box 44'. Air and water is supplied to all handpieces through the air and water control box 51 connected to box 44' and the air and water supplies 120, 122 connected to box 51.

FIG. 14 shows a system S which is similar to system S4 but is enlarged to include another single handpiece HP4 carried by a single switch and hanger box b. An additional air and water distribution box 44" is provided for supplying handpiece HP4 with air and water directly from the air and water drive control box 51 when the valves in box 44" are energized. Box 44 is supplied with air and water through normally open and deenergized valves in box 44". Box 44 is supplied with air and water through normally open and deenergized valves in both boxes 44' and 44". The valves in box 44" are arranged as indicated in FIGS. 9-12 for boxes 44 and 44'.

FIG. 15 shows a further enlargement of systems S4 and S5 in which system S6 includes still another single handpiece HPS carried by a single switch and hanger box 300. A further air and water distribution box 440 is provided for supplying air and water to handpiece HPS when the valves in box 44c are energized. Box 44c has three-way air and water valves like boxes 44, 4 4' and 44". When the valves are deenergized in box 44' air and water is supplied directly to normally deenergized valves in box 44 which when deenergized supply air and Water to box 44. It will be apparent that the systems could be further enlarged to include any larger number of fluiddriven handpieces by including further air and water distribution boxes having solenoid controlled valves in which normally open passages exist while the valves are deenergized. The enlarged systems could also include a dental engine mechanically driving a low-speed hightorque handpiece if desired as described in connection with systems S1 and S3.

In all systems, the dentist has conveniently mounted on a dental stand, wall, dental chair or other support, one or more switch and hanger boxes so that he can select at will any fluid-driven handpiece for instant use. The boxes can be mounted on swingable arms to be moved out of the way of the patient and of the dentists immediate work area, yet they will also be still available for hanging a handpiece on a box or removing a handpiece therefrom. Only the particular selected handpiece can be operated. All other handpieces remain inactive. The dental systems described can be installed as accessories to existing dental treatment apparatus or can be integrated in such equipment as parts of an original installation.

While I have illustrated and described the preferred embodiments of my invention, it is to be understood that I do not limit myself to the precise constructions herein disclosed and that various changes and modifications may be made within the scope of the invention as defined in the appended claims.

Having thus described my invention, what I claim as new, and desire to secure by United States Letters Patent 1. A dental treatment appliance assembly, comprising a switch and hanger box, means on said box for mounting the same at a Working position of a dentist, a movable hanger extending outwardly of said box, an air-driven handpiece removably mounted on the hanger, a switch in said box oper-atively coupled to the hanger for actuation when the handpiece is removed from the hanger; a fluid distribution and control box, means on the control box for mounting the same at a position remote from the switch and hanger box out of the way of said working position of the dentist, a supply source of air under pressure external of said control box, a solenoid operated air valve in the control box, a conduit connecting said air supply source and said valve to supply pressurized air thereto, a supply source of water under pressure external of said control box, a solenoid operated water valve in the control box, a water supply conduit connecting said water supply source and said water valve to supply water under pressure thereto, an air conveying conduit connecting said air valve and said handpiece for driving the same,

- a water conveying conduit connecting said water valve and said handpiece for supplying coolant water thereto, a

power supply, electric current conducting lines connecting said power supply, sai-d switch and said valves for actuating the valves to supply air and water to the handpiece when the handpiece is lifted from said hanger, and foot operable control means fo-r'controlling supply of air andwater to the handpiece.

2. A dental treatment appliance assembly, comprising a switch and hanger box, means on said box for mounting the same at a working position of a dentist, a movable hanger extending outwardly of said box, an air-driven handpiece removably mounted on the hanger, a switch in said box operatively coupled to the hanger for actuation when the handpiece is removed from the hanger; a fluid distribution and control box, means on the control box for mounting the same at a position remote from the switch and hanger box out of the way of said working position of the dentist, a supply source of air under pressure external of said control box, a solenoid operated air valve in the control box, a conduit connecting said air supply source and said valve to supply pressurized air thereto, a supply source of water under pressure external of said control box, a solenoid operated water valve in the control box, a water supply conduit connecting said water supply source and said water valve to supply water under pressure thereto, an air conveying conduit connecting said air valve and said handpiece for driving the same, a water conveying conduit connecting said water valve and said handpiece for supplying coolant water thereto, a

power supply, electric current conducting lines connecting said power supply, said switch and said valves for actuating the valves to supply air and water to the handpiece when the handpiece is lifted from said hanger, and foot operable control means in circuit with said lines for controlling supply of electric current to the valves when the handpiece is lifted from the hanger to control supply of air and water to the handpiece.

3. A dental treatment appliance assembly, comprising a switch and hanger box, means for mounting said box at a working position of a dentist, a pair of movable hangers extending outwardly of said box, air-driven handpieces removably mounted on the respective hangers, switches in said box operatively coupled to the hangers respectively for individual actuation when either handpiece is removed from one of the hangers; a fluid distribution box mountable at a position remote from the switch and hanger box and out of the way of said working position of the dentist, a supply source of air under pressure external of said distribution box, solenoid operated air valve means in the distribution box, an air conduit connecting said air supply source and said air valve means to supply pressurized air thereto, air conducting conduits connected to said air valve means and to said handpieces respectively for selectively supplying pressurized air to either handpiece when the associated switch in the switch and hanger box is actuated, a supply source of water under pressure external of said distribution box, solenoid operated water valve means in the distribution box, a water conduit connecting said water supply source and said water valve means to supply water under pressure thereto, water conducting conduits connected to said water valve means and to said handpieces respectively for selectively supplying pressurized water to either handpiece when the associated switch in the switch and hanger box is actuated, a power supply, and electric current conducting lines connecting said power supply, said switches and said valve means for selectively actuating the valves to supply air and water to either one of the handpieces when the one handpiece is lifted fro-m its hanger.

4. A dental treatment appliance assembly, comprising a switch and hanger box, means for mounting said box at a working position of a dentist, a pair of movable hangers extending outwardly of said box, two air-driven handpieces removably mounted on the respective hangers, at least one switch in said box operatively coupled to one of the hangers for actuation when one handpiece is removed from its hanger; a fluid distribution box mountable at a position remote from the switch and hanger box and out of the way of said working position of the dentist, a supply source of air under pressure external of said distribution box, foot-controlled means associated with said supply source of air for controllably passing air therefrom, a solenoid operated air valve in the distribution box, said air valve having an air inlet and two air outlets, a first air outlet being normally in communication with the air inlet when the solenoid is deenergized, the second air outlet being connected in communication with the air inlet and the first air outlet being closed when the solenoid is deenergized, an air conduit connecting said air supply source to the inlet of said air valve to supply pressurized air thereto, two other air conducting conduits connected from the two air outlets to the two handpieces respectively, a power supply, electric current conducting lines connecting said power supply, said solenoid and switch so that the solenoid is energized to actuate said air valve only when the one handpiece is lifted from its hanger to close the first outlet and open the second outlet and pass air to the one handpiece when the foot-controlled means is operated, and so that only the other handpiece receives air via the normally open first air outlet while the solenoid remains deenergized, while the one handpiece remains on its hanger and while the foot-controlled means is operated.

5. A dental treatment appliance assembly according to 10 claim 4, further comprising a supply source of fluid coolant under pressure external of said distribution box and associated with foot-controlled means for controllably passing fluid coolant from its supply source, another solenoid operated valve in the distribution box, said other valve having a fluid inlet and two air outlets, a first fluid outlet being normally in communication with the fluid inlet when the other solenoid is deenergized, the second fluid outlet being connected in communication with the fluid inlet and the first fluid outlet being closed-when the other solenoid is deenergized, a fluid conduit connecting said fluid supply source to the fluid inlet of said other valve to supply pressurized fluid thereto, two other fluid conducting conduits connected from the two fluid outlets to the two handpieces respectively, other electric current conducting lines connecting said power supply, the solenoid of the other valve and said switch so that the other solenoid is energized to actuate said other valve only when the one handpiece is lifted from its hanger to close the first fluid outlet and open the second fluid outlet and pass fluid to the one handpiece when the foot-controlled means is operated, and so that only the other handpiece receives fluid via the normally open first fiuid outlet while the solenoid of the other valve remains deenergized, while the one handpiece remains on its hanger and while the foot-controlled means is operated.

6. A dental treatment appliance assembly, comprising a switch and hanger box, means for mounting said box at a working position of a dentist, a pair of movable hangers extending outwardly of said box, two air-driven handpieces removably mounted on the respective hangers, at least one switch in said box operatively coupled to one of the hangers for actuation when one handpiece is removed from its hanger; a fluid distribution box mountable at a positionremote from the switch and hanger box and out of the way of said working position of the dentist, a supply source of air under pressure external of said distribution box, foot-controlled means associated with said supply source of air for controllably passing air therefrom, a solenoid operated air valve in the distribution box, said air valve having an air inlet and two air outlets, a first air outlet being normally in communication with the air inlet when the solenoid is deenergized, the second air outlet being connected in communication with the air inlet and the first air out-let being closed when the solenoid is deenergized, an air conduit connecting said air supply source to the inlet of said air valve to supply pressurized air thereto, two other air conducting conduits connected from the two air outlets to the two handpieces respectively, a power supply, electric current conducting lines connecting said power supply, said solenoid and switch so'that the solenoid is energized to actuate said air valve only when the one handpiece is lifted from its hanger to close the first outlet and open the second outlet and pass air to the one handpiece when the foot-controlled means is operated, and so that only the other handpiece receives air via the normally open first air outlet while the solenoid remains deenergized, while the one handpiece remains on its hanger and while the foot-controlled means is operated, said supply source of air including a further solenoid controlled valve, and another switch in said switch and hanger box operatively coupled to the other hanger removably supporting the other handpiece, the switches in said switch and hanger box being both connected in circuit with said further solenoid so that said further solenoid is actuated to pass air from said supply source when either handpiece is lifted from its hanger.

7. A dental treatment appliance assembly according to claim 4, further comprising a supply source of fluid coolant under pressure external of said distribution box and associated with foot-controlled means for controllably passing fiuid coolant from its supply source, another solenoid operated valve in the distribution box, said other valve having a fluid inlet and two air outlets, a first fluid outlet being normally in communication with the fluid inlet when the other solenoid is deenergized, the second fluid outlet being connected in communication with the fluid inlet and the first fluid outlet being closed when the other solenoid is deenergized, a fluid conduit connecting said fluid supply source to the fluid inlet of said other valve to supply pressurized fluid thereto, two other fluid conducting conduits connected from the two fluid outlets to the two handpieces respectively, other electric current conducting lines connecting said power supply, the solenoid of the other valve and said switch so that the other solenoid is energized to actuate said other valve only when the one handpiece is lifted from its hanger to close the first fluid outlet and open the second fluid outlet and pass fluid to the one handpiece when the foot-controlled means is operated, and so that only the other handpiece receives fluid via the normally open first fluid outlet while the solenoid of the other valve remains deenergized, while the one handpiece remains on its hanger and while the foot-controlled means is operated, said supply source of air including another solenoid controlled air valve, said supply source of fluid including another solenoid controlled fluid valve, and another switch in said switch and hanger box operatively coupled to the other hanger removably supporting said other handpiece, the switches in said switch and hanger box being both connected in circuit with the solenoids of both the solenoids of the other air and fluid valves so that the last-named valves are actuated to pass air and fluid from the supply sources thereof when either handpiece is lifted from its hanger.

8. A dental treatment appliance assembly, comprising at least three fluid-driven handpieces, at least three hangers removably supporting said handpieces respectively, a first solenoid operated fluid distribution valve having a fluid inlet and two fluid outlets, a first one of the two outlets being normally connected in communication with the fluid inlet when the solenoid is deenergized, a second one of the two outlets being connected in communication with the fluid inlet when the solenoid is energized, fluid conductors connecting two of the handpieces directly to the two fluid outlets respectively, a second solenoid operated fluid distribution valve having another fluid inlet and two other fluid outlets, a first one of the other fluid outlets being normally connected in communication with the other fluid inlet when the solenoid of the second valve is deenergized and being further connected to the fluid inlet of the first valve to supply fluid thereto, a secnd one of the two other fluid outlets being connected in communication with the other fluid inlet when the solenoid of the second valve is energized, said other fluid outlet being connected to the third handpiece, a first switch associated with one of the two handpieces and actuated when said one handpiece is lifted from its hanger, a second switch associated with the third handpiece, a source of fluid connected to the other'inlet of the second valve, electric current conducting lines connecting the first switch with the solenoid of the first valve and connecting the second switch in circuit with the solenoid of the second valve, and a power supply connected in said circuit, whereby either of said two handpieces when lifted from its hanger will receive fluid from said source via the first and second valves, and whereby the third handpiece will receive fluid from said source via only the second valve when the third handpiece is lifted from its hanger while fluid supply to the two handpieces is cut off at the second valve.

9. A dental treatment appliance assembly, comprising two fluid-driven handpieces, two hangers removably supporting said handpieces respectively, a solenoid operated fluid distribution valve having a fluid inlet and two fluid outlets, a first one of the two outlets being normally connected in communication with the fluid inlet when the solenoid is deenergized, a second one of the two outlets being connected in communication with the fluid inlet when the solenoid is energized, fluid conductors connecting the two handpieces directly to the two fluid outlets respectively, a fluid supply source connected to the fluid inlet of the valve, a switch associated with one of the hangers supporting one of the handpieces, a power supply connecting said switch in circuit with said solenoid and switch, and footoperated means for cont-rolling passage of fluid from said fluid source, whereby said one handpiece receives fluid from said source under control of said foot-operated means when the one handpiece is lifted from its hanger and said valve is actuated to close the first outlet and open the second outlet, and whereby the other handpiece receives fluid from said source under control of said foot-operated means and via said first outlet in the valve when the other handpiece is lifted from its hanger and said solenoid remains deenergized.

10. A dental treatment appliance assembly, comprising two fluid-driven handpieces, two hangers removably supporting said handpieces respectively, a solenoid operated fluid distribution valve having a fluid inlet and two fluid outlets, a first one of the two outlets being normally connected in communication with the fluid inlet when the solenoid is deenergized, a second one of the two outlets being connected in communication with the fluid inlet when the solenoid is energized, fluid conductors connecting the two handpieces directly to the two fluid outlets respectively, a fluid supply connected to the fluid inlet of the valve, aswitch associated with one of the hangers supporting one of the handpieces, a power supply connecting said switch in circuit with said solenoid and switch, and foot-operated means for controlling passage of fluid from said fluid source, whereby said one handpiece receives fluid from said source under control of said foot-operated means when the one handpiece is lifted from its hanger and said valve is actuated to close the first outlet and open the second outlet, and whereby the other handpiece receives fluid from said source under control of said foot-operated means and via said first. outlet in the valve when the other handpiece is lifted from its hanger and said solenoid remains deenergized, said fluid supply source having an electrically operable valve, another switch associated with the hanger removably supporting said other handpiece, the first-named and other switch being connected in circuit with said electrically operable valve and said power supply so that said fluid supply source passes fluid to the fluid distribution valve when either handpiece is lifted from its hanger and said foot-operated means is actuated.

11. A dental treatment appliance assembly, comprising at least three fluid-driven handpieces, at least three hangers removably supporting said handpieces respectively, a first solenoid operated fluid distribution valve having'a fluid inlet and two fluid outlets, a first one of the two outlets being normally connected in communication with the fluid inlet when the solenoid is deenergized, a second one of the two outlets being connected in communication with the fluid inlet when the solenoid is energized, fluid conductors connecting two of the handpieces directly to the two fluid outlets respectively, a second solenoid operated fluid distribution valve having another fluid inlet and two other fluid outlets, a first one of the other fluid outlets being normally connected in communication with the other fluid inlet when the solenoid of the second valve is deenergized and being further connected to the fluid inlet of the first valve to supply fluid thereto, a second one of the two other fluid outlets being connected in communication with the other fluid inlet when the solenoid of the second valve is energized, said other fluid outlet being connected to the third handpiece, a first switch associated with one of the two handpieces and actuated when said one handpiece is lifted from its hanger, a second switch associated with the third handpiece, a source of fluid connected to the other inlet of the second valve, electric current conducting lines connecting the first switch with the solenoid of the first valve and connecting the second switch in circuit with the solenoid of the second valve, a power supply connected in said circuit, whereby either of said two handpieces when lifted from its hanger will receive fluid from said source via the first and second valves, and whereby the third handpiece will receive fluid from said source via only the second valve when the third handpiece is lifted from its hanger while fluid supply to the two handpieces is cut otf at the second valve, and a footoperated means associated with said fluid supply source for controlling passage of fluid therefrom when any handpiece is lifted from its hanger.

12. A dental treatment appliance assembly, comprising at least three fluid-driven handpieces, at least three hangers removably supporting said handpieces respectively, a first solenoid operated fluid distribution valve having a fluid inlet and two fluid outlets, a first one of the two outlets being normally connected in communication with the fluid inlet when the solenoid is deenergized, a second one of the two outlets being connected in communication with the fluid inlet when the solenoid is energized, fluid conductors connecting two of the handpieces directly to the two fluid outlets respectively, a second solenoid operated fluid distribution valve having another fluid inlet and two other fluid outlets, a first one of the other fluid outlets being normally connected in communication with the other fluid inlet when the solenoid of the second valve is deenergized and being further connected to the fluid inletof the first valve to supply fluid thereto, a second one of the two other fluid outlets being connected in communication with the other fluid inlet when the solenoid of the second valve is energized, said other fluid outlet being connected to the third handpiece, a first switch associated with one of the two handpieces and actuated when said one handpiece is lifted from its hanger, a second switch associated with the third handpiece, a source of fluid connected to the other inlet of the second valve, electric current conducting lines connecting the first switch with the solenoid of the first valve and connecting the second switch in circuit with the solenoid of the second valve, a power supply connected in said circuit, whereby either of said two handpieces when lifted from its hanger will receive fluid from said source via the first and second valves, and whereby the third handpiece will receive fluid from said source via only the second valve when the third handpiece is lifted from its hanger while fluid supply to the two handpieces is cut off at the second valve, a foot-operated means associated with said fluid supply source for controlling passage of fluid therefrom when any handpiece is lifted from its hanger, and a third switch associated with the hanger supporting the other of the two handpieces, said fluid supply source including an electrically operable valve connected in electric circuit with said power supply and each of the three switches, whereby said fluid supply source passes fluid to the second valve only when a handpiece is lifted from its hanger to actuate its associated switch.

13. In a dental treatment appliance assembly, in combination, a switch and hanger box, means for mounting said box at a working position of a dentist, a pair of movable hangers extending outwardly of said box, two fluid-driven handpieces removably mounted on the respective hangers, and switches in said box operatively coupled to the hangers respectively for actuation when either handpiece is removed from its hanger, said switches having one position when the handpieces are on the hangers for passing electric current in a power supply circuit to energize a dental engine, said switches having another position when the handpieces are lifted from the hangers for passing current to electrically operated valves 14 for passing fluid only to the particular handpiece lifted from its hanger,

14, In a dental treatment appliance assembly, in conibination, a switch and hanger box, means for mounting said box at a working position of a dentist, a pair of movable hangers extending outwardly of said box, two fluid-driven handpieces removably mounted on the respective hangers, and switches in said box operatively coupled to the hangers respectively for actuation when either handpiece is removed from its hanger, said switches having one position when the handpieces are on the hangers for passing electric current in a power supply circuit to energize a dental engine, said switches having another position when the handpieces are lifted from the hanger to open said power supply circuit, and an electrically operable fluid distribution valve having two outlets, one of the outlets being normally open when the valve is deenergized while the other outlet is closed, the other outlet being open when the valve is energized while the one outlet is closed, said outlets being connected to the headpieces respectively, one of the switches being connected to said valve to operate the same when one head piece carried by one hanger associated with said one switch is lifted for supplying fluid to said one handpiece, the other handpiece being supplied with fluid via the normally open one outlet when the other handpiece is lifted from its hanger while the valve remains electrically deenergized and the other outlet remains closed.

15. A dental treatment appliance assembly, comprising a switch and hanger box, means on said box for mounting the same at a working position of a dentist, a movable hanger extending outwardly of said box, an airdriven handpiece removably mounted on the hanger, a switch in said box operatively coupled to the hanger for actuation when the handpiece is removed from the hanger; a fluid distribution box, means on the distri bution box for mounting the same at a position remote from the switch and hanger box out of the way of said working position of the dentist, a supply source of air under pressure external of said fluid distribution box, a solenoid operated air valve in the fluid distribution box,

a conduit connecting said air supply source and said valve to supply pressurized air thereto, a supply source of water under pressure external of said fluid distribution box, a solenoid operated water valve in the fluid distribution box, a water supply conduit connecting said water supply source and said water valve to supply water under pressure thereto, an air conveying conduit connecting said air valve and said handpiece for driving the same, a water conveying conduit connecting said water valve and said handpiece for supplying coolant water thereto, a power supply, and electric current conducting lines connecting said power supply, said switch and said valves for actuating the valves to supply air and water to the handpiece when the handpiece is lifted from said hanger, said switch having two diiferent operating positions with different contacts at each of the operating positions, certain of said lines being connected to the contacts at one of the switch positions for supplying electric current to a dental engine when the handpiece is mounted on the hanger, others of said lines being connected to the contacts at the other switch position for conducting current to the valves when the handpiece is removed from the hanger.

References Cited by the Examiner UNITED STATES PATENTS 3,049,805 8/1962 Liedberg et al. 32-22 3,209,457 10/1965 Billin et a1. 3222 ROBERT E. MORGAN, Acting Primary Examiner. 

1. A DENTAL TREATMENT APPLIANCE ASSEMBLY, COMPRISING A SWITCH AND HANGER BOX, MEANS ON SAID BOX FOR MOUNTING THE SAME AT A WORKING POSITION OF A DENTIST, A MOVABLE HANGER EXTENDING OUTWARDLY OF SAID BOX, AN AIR-DRIVEN HANDPIECE REMOVABLY MOUNTED ON THE HANGER, A SWITCH IN SAID BOX OPERATIVELY COUPLED TO THE HANGER FOR ACTUATION WHEN THE HANDPIECE IS REMOVED FROM THE HANGER; A FLUID DISTRIBUTION AND CONTROL BOX, MEANS ON THE CONTROL BOX FOR MOUNTING THE SAME AT A POSITION REMOTE FROM THE SWITCH AND HANGER BOX OUT OF THE WAY OF SAID WORKING POSITION OF THE DENTIST, A SUPPLY SOURCE OF AIR UNDER PRESSURE EXTERNAL OF SAID CONTROL BOX, A SOLENOID OPERATED AIR VALVE IN THE CONTROL BOX, A CONDUIT CONNECTING SAID AIR SUPPLY SOURCE AND SAID VALVE TO SUPPLY PRESSURIZED AIR THERETO, A SUPPLY SOURCE OF WATER UNDER PRESSURE EXTERNAL OF SAID CONTROL BOX, A SOLENOID OPERATED WATER VALVE IN THE CONTROL BOX, A WATER SUPPLY CONDUIT CONNECTING SAID WATER SUPPLY SOURCE AND SAID WATER VALVE TO SUPPLY WATER UNDER PRESSURE THERETO, AN AIR CONVEYING CONDUIT CONNECTING SAID AIR VALVE AND SAID HANDPIECE FOR DRIVING THE SAME, A WATER CONVEYING CONDUIT CONNECTING SAID WATER VALVE AND SAID HANDPIECE FOR SUPPLYING COOLANT WATER THERETO, A POWER SUPPLY, ELECTRIC CURRENT CONDUCTING LINES CONNECTING SAID POWER SUPPLY, SAID SWITCH AND SAID VALVES FOR ACTUATING THE VALVES TO SUPPLY AIR AND WATER TO THE HANDPIECE WHEN THE HANDPIECE IS LIFTED FROM SAID HANGER, AND FOOT OPERABLE CONTROL MEANS FOR CONTROLLING SUPPLY OF AIR AND WATER TO THE HANDPIECE. 